Impact of Chemotherapy and Radiotherapy on the Success of Cerebrospinal Fluid Leak Repair after Transnasal Endoscopic Resection of Skull Bases Tumors

Background: Transnasal endoscopic resection (TER), whether purely endoscopic or endoscopic-assisted, has become the treatment approach of choice for many skull base tumors. Potential benefits of TER include decreased morbidity and improved cosmetic results. One of the major limitations of TER is the management of large dural defects and the need for repair of cerebrospinal fluid (CSF) leaks. This is a major consideration for patients who are treated with neoadjuvant or adjuvant chemotherapy (CTX) and radiotherapy (RTX), as these modalities can impair wound healing and exacerbate surgical complications. With limited studies in the published literature, it is unclear whether TER is associated with an increased risk of failed CSF leak repair.

Objective: The objective of this study is to determine the impact of CTX and RTX on the success of CSF leak repair after TER.

Methods: We conducted a retrospective chart review of a single institution's experience with TER from 1992–2011.

Results: Twenty-eight patients were identified to have CSF leak after TER for malignant skull base tumors. Of these, 18 patients underwent RTX and 9 patients were treated with CTX. All patients required CSF leak repair after cribriform and/or dural resection with mucosal flaps or pericranial flaps. Failed CSF leak repair was noted in three patients (10.7%). These patients showed an increased risk of other neurological sequelae, including altered mental status, seizure, and meningitis (P = 0.017). A prior history of RTX or CTX (28.57%) was not associated with the risk of failed CSF leak repair.

Conclusion: Adjuvant or neoadjuvant CTX or RTX is not associated with an increased risk of failed CSF leak repair. Our 10% incidence compares favorably with currently published literature. Careful selection of the appropriate candidate for TER can limit the devastating neurological sequelae associated with a failed repair. Moreover, failed repairs can delay the initiation of adjuvant therapies. Successful CSF leak repair can be performed in patients with malignant skull base tumors with an acceptable risk profile.